JPH0286B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a filter cloth elevating device for a pressure filter.

[Conventional technology]

In this type of pressure filter, the material to be filtered is filtered through a filter cloth between a large number of parallel filter plates, and then the filter cloth after pressure filtration is lowered as the frame is opened to remove the cake. After falling and peeling off, the filter cloth is raised for cleaning and refiltration operations, and as a means for raising and lowering the filter cloth, a filter cloth lifting device is provided one-to-one for each filter plate. is attached.

This filter cloth elevating device is disclosed in Japanese Patent Application Laid-open No. 55-54007 proposed by the present applicant, in which a movable pulley at the tip of the piston cylinder is moved by the expansion and contraction of the rod of the piston cylinder, and the filter cloth is wrapped around a fixed and movable pulley. There is one that raises and lowers the filter cloth through a string body.
It is widely used due to its simple structure.

[Problem that the invention seeks to solve]

As mentioned above, the number of filter cloth lifting devices is basically the same as that of each filter plate, and the number thereof is extremely large. If all the filter cloth cakes are peeled off at once, the belt conveyor placed below the filter cloth will be overloaded, leading to operational problems. Therefore, the filter cloth should be lowered one by one or in small numbers. This must be done in conjunction with the isolation of the filter plate group.

In this case, it is conceivable to install solenoid valves in the hydraulic system from the pressure oil source to each piston cylinder to switch the operation of the piston cylinders for raising and lowering the filter cloth. This resulted in a non-negligible increase in the cost of the entire pressure filter. In addition, when operating this solenoid valve, in order to prevent overloading of the belt conveyor, as mentioned above, the filter cloth is lowered when the frame is opened or the gap between the filter plates exceeds a specified value. Since it is necessary to start the process, a large number of sensors are required to detect the opening of the frame or the gap between the filter plates, and a control panel is also required to send signals from these sensors to the solenoid valve, which also increases costs. Ta. Furthermore, solenoid valves often break down and pose many maintenance problems.

Therefore, the main object of the present invention is to mechanically open and close the pressure fluid path to the piston cylinder that moves the filter cloth up and down in conjunction with the isolation operation that is performed one by one or a few filter plates between the filter plates. It is an object of the present invention to provide a device for lifting and lowering a filter cloth which is highly reliable and extremely economical in terms of equipment.

[Means for solving problems]

To solve the above problems, the present invention provides a filter cloth elevating device for elevating and lowering a filter cloth between a large number of filter plates; A pressure medium working path and a pressure medium return path are provided in parallel from the source to each of the piston cylinders through one main valve, and a pressure medium flow path connecting the main valve and the piston cylinder is provided in each valve block. A communication passage forming a part of the operation is formed, a valve element is provided in the communication passage to open and close the communication passage according to the action and non-action of pressure fluid pressure, and an operating member is provided to move the communication passage in opposition to the valve element. The filter is configured to be movable, and the movement of the operating member moves the valve body to switch the communication state of the communicating passage, and the operating member is moved one by one or one by one for each small number of filters. It is characterized in that it is mechanically driven by the separating operation between the plates.

[Effect]

In the present invention, a valve block is provided between the pressure source and the piston cylinder for raising and lowering the filter cloth, and a valve body is provided in the communication passage for opening and closing the communication passage in accordance with the action and non-action of the pressure fluid pressure. Therefore, even if the pump attached to the pressure source is stopped, the filter cloth can be maintained in the raised state, for example. However, only the valve body having this check valve function can perform only one of the lifting and lowering operations of the filter cloth. For example, when fluid pressure is applied to one port of a reciprocating piston cylinder from a pressure source through a communication passage of a valve block so that the filter cloth rises when fluid pressure is applied to the piston cylinder, the filter In order to lower the cloth, it is necessary to release the pressure fluid at the appropriate time during the separation between the filter plates. In order to release this pressure fluid, another valve body is required, and some means is required to provide the valve body with the release timing.

In contrast, in the present invention, the valve body having the above-mentioned check valve function also functions as a valve body that triggers release of pressure fluid. As a specific means for this, the valve body is provided with operating members facing each other, and this operating member is configured to follow the isolation movement between the filter plates, so that the filter plates are isolated and the operating member moves. When the valve body moves along with the movement,
The open/close state of the communication path can be switched.

As described above, the valve device for switching up and down the filter cloth in the present invention is mechanical, and is highly reliable and inexpensive. Moreover, when the filter cloth is switched from the raised state to the lowered state, the operating member is driven and switched in accordance with the isolation operation between the filter plates, so there is a separate electrical connection that detects the isolation state between the filter plates. This eliminates the need for additional sensors, making it extremely economical. Further, by performing such a sequential lowering operation of the filter cloth, overloading of the cake discharge belt conveyor is prevented.

〔Example〕

The present invention will be explained in more detail below with reference to Examples.

First, to describe the filter as a whole, this filter has a large number of filter plates 1 arranged in parallel and a filter cloth 2 arranged between them so as to be able to move up and down, and the slurry to be treated is passed between the filter cloths 2. After the filter cloth is supplied to the surface of the filter cloth, it is pressed through the movable frame 81 at one end and the filter plate 1 by a hydraulic cylinder 80 (see Fig. 7) arranged in a direction perpendicular to the surface of the filter cloth 2, and after performing a filtration operation, the filter cloth at one end is The movable frame 81 is sequentially indexed and opened by an indexing mechanism associated with each filter plate along the length direction of the filter, and at this time, the filter cloth 2 is lowered and the cake remaining between the filter cloths 2 is peeled off. After that, when all the cakes have finished falling, the filter cloth 2 is raised, the filter cloth 2 is washed at that time, and the space between each filter plate 1 is tightened to return to the original operation. There is.

To explain in detail the structure of the entire pressure filter, the pedestal 8
A beam member 84 is arranged between the filter plates 1 and 83 on both sides of each filter plate 1 and 1 (both sides in the direction penetrating the plane of the paper in FIG. 7), and a frame 83 is provided with a hydraulic cylinder 80 for closing and opening the frame. , the expansion and contraction motion by this hydraulic cylinder 80 is transmitted to the moving frame 81. Furthermore, a support member 85 is provided on the moving frame 81 and each of the filter plates 1, 1, . It is placed there.

Therefore, when opening the frame, the hydraulic cylinder 80
As the rods extend, each filter plate 1 is sequentially closed from the right to the left in FIG. 7 via the moving frame 81. When opening the frame, as the rod of the hydraulic cylinder 80 contracts, the movable frame 81 moves to the right in FIG. When the frame is opened from the plate 1 and the frame advances and the stop end of the connecting rod 86 comes into contact with the supporting member 85 which is integrated with the adjacent filter plate 1, the index moves to the right of the adjacent filter plate 1. Begins. In this way, the opening is performed sequentially starting from the right filter plate 1.

On the other hand, both of the patent applications filed in 1983 are
As in No. 54007 and No. 55-75711, a filter cloth 2 comprising a pair of unit filter cloths 2a and 2b suspended by wires 7 is provided between adjacent filter plates 1 and 1,
The lower end of each unit filter cloth 2a, 2b is connected to the opposing filter plate 1,
Winding rolls 8 each integrally provided in 1.
7, 87, and as clearly shown in FIGS. 7 to 10, the filter cloth 2
It is configured such that it can be raised and lowered, and wound up and fed out onto a winding roll 87.

In this embodiment, in order to raise and lower the filter cloth 2 mentioned above, the above-mentioned Japanese Patent Application Laid-Open No. 55-54007, filed by the present applicant, is used.
As with the one described in the publication, the piston cylinder 3
A pulley type drive system is used. That is, as shown in FIGS. 4 and 5, a hydraulic double-acting piston cylinder 3 is fixed one-to-one on each filter plate 1, 1, etc. via a frame 4, and is moved to the tip of the cylinder rod. A pulley 5 is rotatably attached, and on the other hand, a fixed pulley 6 is rotatably attached to the back of the piston cylinder 3 by a common frame 4. Further, the filter cloth 2 is suspended by a wire 7, and this wire 7 passes through a fixed pulley 6, a movable pulley 5, and again a fixed pulley 6 to reach the valve block 1.
It is connected to the tip of the secondary lever 40 of No. 0 via a wire anchor 70. 8 is a mounting member for the valve block 10.

The switching operation of the piston cylinder 3 for raising and lowering the filter cloth 2 is performed by a valve block 10 and a collecting block 20, details of which are shown in FIGS. 1 to 3. The valve block 10 has its upper and lower openings 1.
1 and 12 are formed, and these are connected to form a communication path 13.
A, 13B, 13C, and 13D are formed.
Further, a main ball valve 14, a needle valve 15, and an auxiliary ball valve 16 are provided horizontally across the communication path from the opening 11 to the opening 12 at the upper, middle, and lower stages, respectively. The needle valve 15 is arranged between the ball valves 14 and 16 for the purpose of compactness. In the main ball valve 14, a ball 14d, which serves as a valve body according to the present invention, is urged toward a stepped portion 14c by a spring 14b seated on a plug 14a. When no external force is applied by the main plunger 17, which will be described below, the main plunger 17 is located at the imaginary line position in FIG. . On the other hand, when hydraulic pressure that overcomes the biasing force of the spring 14b acts from the opening 11 side, the ball 14d is retreated to the solid line position in FIG.
Oil flows towards 2.

On the other hand, a main plunger 17, which serves as an operating member according to the present invention, is provided opposite the ball 14d of the main ball valve 14. This main plunger 17
A piston 17a having an O-ring is provided with rod portions 17b and 17c at both ends, and one end of the rod portion 17c protrudes from the surface of the valve block 10.

The structure of the main ball valve 14 is directly applicable to the auxiliary ball valve 16, so the numeral 1
The same lowercase alphabetic character will be added after 6, and further explanation will be omitted. The same applies to the sub-plunger 18.

The needle valve 15 includes a needle 15a having a male thread and a piston 15b having an O-ring, which are arranged with a communication path in between.
5c, and one end of the piston 15b protrudes from the surface of the valve block 10, and an insertion groove 1 for driver operation is formed therein.
5d is formed. 15e is a blind plug. In this needle valve 15, the insertion groove 15
By inserting the tip of a screwdriver into the hole d and rotating the piston 15b, the needle 15a is screwed back and forth accordingly, thereby adjusting the amount of oil passing through the communication path depending on the degree to which the needle 15a partitions the communication path. ,
The lifting speed of the filter cloth 2 is controlled.

The above valve block 10 includes a collection block 20.
are attached on a one-to-one basis. Channels 21 and 22 are perforated in the collecting block 20 in the vertical direction at different positions, passing through one and halfway through the other.
The upper end is blinded by blind plugs 23 and 24. Further, an inlet 25 and an outlet 26 are formed facing the guide path 21, and an inlet 27 and outlets 28, 29 are formed facing the guide path 22.

On the other hand, a main lever 30 and an auxiliary lever 40 are pivotally connected to the valve block 10, facing the rod portions 17c and 18c of the main plunger 17 and the auxiliary plunger 18, respectively. The main lever 30 has a substantially L-shape, and is rotatably pivoted in the middle by a pin 52 that is pivotally supported by two brackets 51, and its abdomen is connected to the rod portion 17c of the main plunger 17. is facing. Secondary lever 4
0, as previously shown in FIGS. 4 and 5,
The main lever 30 is pivotally mounted to be rotatable in the plane of the paper, and as shown in FIG. The tips are sequentially connected by operation springs 61, 62, 63, . . . .

Furthermore, as shown in FIG.
An oil tank 100, a hydraulic pump 101, and a three-way solenoid valve 102 as a main valve according to the present invention are arranged, and two outlet ports of the three-way solenoid valve 102 are connected to the filter cloth lifting means of the preceding system A. It is connected to the inlets 27A and 25A of the collecting block 20, and the outlet 2
8A, 26A are the entrances 27B, 25B of the following B system
The hydraulic hose 60 is connected to the hydraulic hose 60, and the same is true thereafter. As a result, parallel hydraulic action paths and oil return paths are formed for each piston cylinder 3A, 3B, . . . .

In the filter cloth elevating device configured as described above, the following operations are performed. That is, when the filtration operation is completed, the electromagnetic valve 102 is switched to the X side at the stage where the clamping between the filter plates 1 and 1 is released in order to peel off the cake attached to the filter cloth.
As a result, oil tends to flow from the inlet 27A through the outlet 29A to the descending port D of the piston cylinder 3A. At this time, the filter cloth 2A is attached to the wire 7.
Although the secondary lever 40 is always tilted due to its own weight and the biasing force of the lower take-up roll 87, and the ball 16d is pushed by the movement of the secondary plunger 18, and the communication path is opened. Since the spring 61 is not pulled and as a result, the main lever 30A is separated from the main plunger 17, the ball 14d is pressed against the stepped portion 14c by the urging force of the spring 14b of the ball valve 14, so that the communication path is closed. is closed. Therefore, the oil from the rising port U of the piston cylinder 3A cannot return to the oil tank 100, and the piston cylinder 3A remains stopped.

Thereafter, when the preceding filter plate (the one on the open frame side of the filter plate 1A) is separated from the filter plate 1A by a certain length, the spring 61 expands with the separation, and the main lever 3
Since the butt of the main lever 30A is pulled, the main lever 30A rotates around its pin 52 so that its tip is tilted toward the valve block 10, thereby pressing the main plunger 17 with its belly. As a result, the ball 14 of the ball valve 14
d is moved, and the communication paths 13B and 13A are opened. As a result, the oil returns to the oil tank 100 from the rising port U, and the movable pulley 5 of the piston cylinder 3A moves to the right in FIG. 2 is lowered by the winding force of the winding roll 87 below it.

During this downward movement, if the filter cloth 2 is caught in the middle, the tension acting on the wire 7 is released, so the sub-lever 40 stands up and the sub-plunger 18
The ball 16d of the ball valve 16 moves to prevent oil from returning and stop the movement of the piston cylinder 3A. Thus, an emergency stop is made to prevent trouble.

Thereafter, when the filter plate 1A is separated from the filter plate 1B by a predetermined distance, the next piston cylinder 3B is activated to lower the filter cloth 2B. Thereafter, similar operations are performed up to the final filter cloth.

When the final cake removal operation on the filter cloth is performed, the solenoid valve 102 is switched to the Y side. Along with this, oil enters the communication path 13A from the opening 11 of the valve block 10 through the conduit 21 from the inlet 25A, and the balls 14d, 1 of the ball valves 14, 16.
6d is pushed away by the oil pressure, and flows into the rising side port U of the piston cylinder 3A. At this time, oil flows out from the descending side port D, and the oil tank 100
The cylinder rod extends and returns as it is.
The moving pulley 5 moves to the left and the filter cloth 2A is pulled up. This lifting operation is performed for all filter cloths 2A, 2
This is done simultaneously for B,... Further, at this time, each of the filter cloths 2A, 2B, . . . is washed with water by a washing pipe (not shown) disposed below. During this cleaning, there is an optimal lifting speed of the filter cloth depending on the remaining state depending on the properties of the cake, so the lifting speed is adjusted by adjusting the position of the needle valve 15 to control the oil amount. Ru. Note that the needle valve 15 can also be used to adjust the descending speed.

When all the filter cloths 2A, 2B, . . . have finished rising, all the filter plates 1A, 1B, . . . are tightened again. This causes each main lever 30A, 30B, . . . to separate from the corresponding main plunger, so that each ball valve 14A, 14B, . . . closes the oil communication path.

The above operations are repeated for each filtration operation.

〔Effect of the invention〕

As described above, according to the present invention, since a mechanical valve device is used instead of an electromagnetic valve to switch up and down each filter cloth, it is inexpensive and can withstand long-term use with high frequency of opening and closing. In addition, because the timing of lifting and lowering, for example, the lowering of a filter cloth, is set according to the isolation operation between filter plates, automatic operation is possible that prevents overload on the cake discharge belt conveyor. This eliminates the need for sensors for detecting isolation status, making it economical in this respect as well.

[Brief explanation of drawings]

Fig. 1 is an overall view of the device of the present invention, Fig. 2 is a sectional view of a part of the valve block, Fig. 3 is a cutaway perspective view of the valve block and the collecting block, and Fig. 4 is a filter cloth lifting device. A front view of the attached state to the plate, Fig. 5 is a right side view thereof, Fig. 6 is a plan view of the connection state of the operating spring for operating the main ball valve, and Fig. 7 is a state before filtrate is supplied after opening the frame. Figure 8 is a front view of the filtration/squeezing state with the frame closed, Figure 9 is a front view of the frame with each chamber opened, and Figure 10 is a front view of the frame with the frame opened and the filter cloth lowered to remove the cake. FIG. 6 is a front view of the discharge completed state. 1, 1A, 1B... filter plate, 2, 2A, 2B...
Filter cloth, 3, 3A, 3B...Piston cylinder, 5
...Moving pulley, 6... Fixed pulley, 7... Wire,
10, 10A, 10B... Valve block, 11, 1
2... Opening, 13A to 13D... Communication path, 14
...Main ball valve, 14b...Spring, 14d
... Ball (valve body), 15 ... Needle valve, 16
... Sub-ball valve, 17... Main plunger (operating member), 18... Sub-plunger, 20... Collection block, 30... Main lever, 40... Sub-lever, 61-64... Operation spring, 100 ……
Oil tank, 101...Hydraulic pump, 102...3-way solenoid valve (main valve).

Claims (1)

[Claims] 1. In a filter cloth elevating device for elevating and lowering a filter cloth between a large number of filter plates; each filter plate is provided with a valve block and a double-acting piston cylinder for elevating and lowering the filter cloth; A pressure medium working path and a pressure medium return path are provided in parallel to each of the piston cylinders via valves, and a part of the pressure medium working path connecting the main valve and the piston cylinder to each of the valve blocks. A communicating path is formed, a valve element is provided in the communicating path to open and close the communicating path according to the action and non-action of pressure fluid pressure, and an operating member is movably provided to move the valve element in opposition to the valve element. , the valve body is moved as a result of the movement of the operating member to switch the communication state of the communication passage, and the operating member is moved one by one or a few filter plates in order to isolate the filter plates. A filter cloth elevating device for a pressure filter, characterized in that it is mechanically driven by.